Set vidargs on colibri-imx8x's u-boot

Simple question here,

What do I write in the vidargs environnement variable in u-boot for colibri imx8qxp?

I tried something like this:
setenv vidargs ‘video=mxcfb0:dev=hdmi,1920x1080M@60,if=RGB24 video=mxcfb1:off fbmem=8’
because it worked on colibri-imx6, but it does not work here

For the moment, I only have an output with VGA but it is a very low resolution (640x480)

I have a colibri evaluation board and the two hdmi adaptater needed for colibri iMX8 and I run with boot2qt

Thanks in advance

The Colibri iMX8X does not have a native HDMI interface. However, there are multiple ways to
implement an HDMI interface on the carrier board.

  • MIPI/DSI to HDMI converter. Since only a single DSI interface is used for 1080p60
    resolution, it is possible to add up to two MIPI/DSI converters to the Colibri iMX8X module.

  • LVDS to HDMI converter. For 1080p60, a dual lane LVDS interface is required. This means,
    only a single HDMI port is possible. In general, a greater number of differential pair LVDS
    signals are required than for a DSI solution.

  • Parallel RGB to HDMI converter. If the 18bit parallel RGB is used, the solution would be
    compatible to other Colibri modules. The resolution is limited to 720p60 due to limitations
    of the parallel interface on the i.MX 8X.

Hi @Romain.Donze

The answer of @alex.tx is correct. Additionally we don’t support vidargs for Colibri iMX8X and you need to define the display interfaces in the devicetree files. There are devicetree files in the toradex_4.14.x kernel branch where either HDMI or LVDS Interface is activated.

Best regards,
Jaski

Ok thanks for your replies.

Answer from @jaski.tx was what I was looking for. Now that I have an output resolution of 1080p via hdmi what will happend if I decide to use a 1280x800 screen? will it scale automatically?

Hi

You are welcome. You can try to set the resolution in the file monitor.xml.

Best regards,
Jaski